Final answer:
The average acceleration of an 87.5-kg sprinter who goes from rest to 11 m/s in 2.8 seconds is calculated using the formula for acceleration (a = change in velocity over time). The acceleration is determined to be 3.93 m/s², which corresponds to option (b).
Step-by-step explanation:
The student asks about calculating the average acceleration of an 87.5-kg sprinter who accelerates from rest to 11 m/s in 2.8 s. Acceleration is defined as the change in velocity divided by the time over which the change occurs. Therefore, to find the sprinter's acceleration, we use the formula:
a = Δv / t
Where a is the acceleration, Δv is the change in velocity, and t is the time interval.
Since the sprinter accelerates from rest, his initial velocity, v₀, is 0 m/s and his final velocity, v₁, is 11 m/s. The time, t, is given as 2.8 s. Plugging these values into the formula gives:
a = (11 m/s - 0 m/s) / 2.8 s
a = 11 m/s / 2.8 s
a = 3.93 m/s²
The answer is (b) 3.93 m/s², which represents the average acceleration of the sprinter over the 2.8 second period.